ABS to PVC threaded union

[brattom]

I am moving a shower drain about one foot, but my house waste system is ABS, and the local code is PVC only. Can't find ABS anywhere. A local plumbing supply store had a connector that is ABS on one side and PVC on the other and the two pieces screw together.

My question is do the threads need to be sealed with anything, or does it just screw together?

Thanks.

Tom

[Cass]

Teflon tape, but, I would use a banded coupling for this transition. They can be had at any plumbing supply store and some of the big box stores.